This is a competing renewal application for a three year two-stage epidemiologic study of the frequency of and risk factors for DSM-III-R major depressive disorder (MDD) and suicidal behavior in late adolescence. The continuation is designed to follow our original middle school screening sample of 3444 students and interview sample of 589 students into late adolescence. Specific objectives are to: (1) estimate the prevalence of MDD, comorbidity, suicide ideation and suicide attempts among twelfth graders; (2) study the incidence and course of depressive disorder, suicide ideation, suicide attempts and comorbidity between early and late adolescence; (3) investigate the relationship between a family history of psychiatric disorder and MDD or suicidal behaviors; (4) explore the relationship between specific types of life events, and specific components of social-family environment and MDD and suicidal behaviors; and, (5) determine the ability of symptoms measured in early adolescence to predict a broad range of adverse outcomes in late adolescence. Data will be collected in the schools via self-administered written questionnaires and in the home via diagnostic interviews. School questionnaires will include depressive symptoms, suicide, life events and family scales as well as information regarding drug and alcohol use, violent behavior, contact with the criminal justice system, use of mental health services, plans for post high school employment and education, impulsivity and self-esteem. All students and parents interviewed during the first three years (1986-1989) of the study as well as a new sample of subjects will be interviewed utilizing the Schedule for Affective Disorders and Schizophrenia in School Age Children. Family history of psychiatric disorder will be ascertained utilizing the Family History-Research Diagnostic Criteria Instrument. Information regarding coping and social support will also be obtained. Diagnoses will be made utilizing DSM-III-R criteria. Results should increase our understanding of the nature and etiology of depression and suicidal behaviors in adolescents.